21686350853 has 16 divisors (see below), whose sum is σ = 23033303040. Its totient is φ = 20360386800.

The previous prime is 21686350841. The next prime is 21686350859. The reversal of 21686350853 is 35805368612.

It is not a de Polignac number, because 21686350853 - 2⁶ = 21686350789 is a prime.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21686350798 and 21686350807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21686350859) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1953308 + ... + 1964378.

It is an arithmetic number, because the mean of its divisors is an integer number (1439581440).

Almost surely, 2^21686350853 is an apocalyptic number.

It is an amenable number.

21686350853 is a deficient number, since it is larger than the sum of its proper divisors (1346952187).

21686350853 is a wasteful number, since it uses less digits than its factorization.

21686350853 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12008.

The product of its (nonzero) digits is 1036800, while the sum is 47.

The spelling of 21686350853 in words is "twenty-one billion, six hundred eighty-six million, three hundred fifty thousand, eight hundred fifty-three".